Medial condyle of tibia – horizontal cavity on the back
3 expansions
forwards along medial surface of condlye deep to the tibial collateral ligament, separated from it by a bursa
obliquely upwards to lateral femoral condyle as the oblique popliteal ligament
strong fascia overlying popliteus & reaches the soleal line of the tibia
Nerve Supply
Action
Semitendinosus
Origin
Medial part of ischial tuberosity
On top of semimebranosus
Insertion
Tendon passes behind the medial condle & then curves forwardes to be inserted behind gracilis into the upper part of the subcutaneous surface of the tibia
Nerve Supply
Action
Biceps femoris
Sciatic nerve is beneath the long head
Origin
Long Head:
In common with semitendinosus
Short Head:
Whole length of linea aspera & upper part of lateral supracondylar line of femur
Insertion
Head of Fibula
Blood Supply of the Hamstrings
Upper
Inferior gluteal artery
Middle (main supply)
Profunda femoris artery & its perforating branches
Lower
Popliteal artery
These arteries form a series of anastomoses along the back of the thigh, the highest being the cruciate anastomosis
Nerve Supply
Tibial component of the sciatic nerve (L5S1)
Ischial part of adductor magnus
All three muscles
Common peroneal nerve
Short head of biceps
Action
Flexion of knee
Extension of hip
With knee semiflexed
biceps femoris is lateral rotator
semitendinosus/membranosus are medial rotators
Sciatic nerve
Passes through long head of biceps & adductor magnus
At popliteal fossa, a hands breath above knee joint it divides into tibial & common peroneal components
Surface Markings –
Midpoint between ischial tuberosity & greater trochanter to the apex of the popliteal fossa
